Characterization of the inflammatory cells in ascending thoracic aortic aneurysms in patients with Marfan syndrome, familial thoracic aortic aneurysms, and sporadic aneurysms.
OBJECTIVE
This study sought to characterize the inflammatory infiltrate in ascending thoracic aortic aneurysm in patients with Marfan syndrome, familial thoracic aortic aneurysm, or nonfamilial thoracic aortic aneurysm.


BACKGROUND
Thoracic aortic aneurysms are associated with a pathologic lesion termed "medial degeneration," which is described as a noninflammatory lesion. Thoracic aortic aneurysms are a complication of Marfan syndrome and can be inherited in an autosomal dominant manner of familial thoracic aortic aneurysm.


METHODS
Full aortic segments were collected from patients undergoing elective repair with Marfan syndrome (n = 5), familial thoracic aortic aneurysm (n = 6), and thoracic aortic aneurysms (n = 9), along with control aortas (n = 5). Immunohistochemistry staining was performed using antibodies directed against markers of lymphocytes and macrophages. Real-time polymerase chain reaction analysis was performed to quantify the expression level of the T-cell receptor beta-chain variable region gene.


RESULTS
Immunohistochemistry of thoracic aortic aneurysm aortas demonstrated that the media and adventitia from Marfan syndrome, familial thoracic aortic aneurysm, and sporadic cases had increased numbers of T lymphocytes and macrophages when compared with control aortas. The number of T cells and macrophages in the aortic media of the aneurysm correlated inversely with the patient's age at the time of prophylactic surgical repair of the aorta. T-cell receptor profiling indicated a similar clonal nature of the T cells in the aortic wall in a majority of aneurysms, whether the patient had Marfan syndrome, familial thoracic aortic aneurysm, or sporadic disease.


CONCLUSIONS
These results indicate that the infiltration of inflammatory cells contributes to the pathogenesis of thoracic aortic aneurysms. Superantigen-driven stimulation of T lymphocytes in the aortic tissues of patients with thoracic aortic aneurysms may contribute to the initial immune response.
He
Rumin
R
Department of Internal Medicine, The University of Texas Medical School at Houston, Houston, Texas 77030, USA.
Guo
Dong-Chuan
DC
Sun
Wei
W
Papke
Christina L
CL
Duraisamy
Senthil
S
Estrera
Anthony L
AL
Safi
Hazim J
HJ
Ahn
Chul
C
Buja
L Maximilian
LM
Arnett
Frank C
FC
Zhang
Jingwu
J
Geng
Yong-Jian
YJ
Milewicz
Dianna M
DM
D000328:Adult; D000368:Aged; D015703:Antigens, CD / Q000276:immunology / Q000378:metabolism; D000945:Antigens, Differentiation, T-Lymphocyte / Q000235:genetics / Q000378:metabolism; D017544:Aortic Aneurysm, Abdominal / Q000276:immunology / Q000473:pathology* / Q000601:surgery; D017545:Aortic Aneurysm, Thoracic / Q000276:immunology / Q000473:pathology* / Q000601:surgery; D015415:Biomarkers / Q000032:analysis; D001707:Biopsy, Needle; D006348:Cardiac Surgical Procedures / Q000379:methods; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008382:Marfan Syndrome / Q000235:genetics / Q000473:pathology* / Q000601:surgery; D008875:Middle Aged; D015999:Multivariate Analysis; D012313:RNA / Q000032:analysis; D011948:Receptors, Antigen, T-Cell / Q000276:immunology* / Q000378:metabolism; D012016:Reference Values; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric; D046509:Tissue Culture Techniques; D053781:Transforming Growth Factor beta2 / Q000032:analysis / Q000276:immunology*; D019010:Vascular Cell Adhesion Molecule-1 / Q000276:immunology / Q000378:metabolism
D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D015415:Biomarkers; D011948:Receptors, Antigen, T-Cell; D053781:Transforming Growth Factor beta2; D019010:Vascular Cell Adhesion Molecule-1; D012313:RNA